The chest x-ray is useful for detecting a number of patient conditions and for imaging a range of skeletal and organ structures. Conventional radiographic images of the chest are useful for detection of lung nodules and other features that indicate lung cancer, other pathologic structures and other life-threatening conditions. In clinical applications such as in the Intensive Care Unit (ICU), chest x-rays can have particular value for indicating pneumothorax as well as for tube/line positioning, and other clinical conditions. To view the lung fields more clearly and allow accurate analysis of a patient's condition, it is useful to suppress the rib cage and related features in the chest x-ray, without losing detail of the lung tissue or other features within the chest cavity.
A different set of considerations applies for trauma patients, particularly with pediatric cases. With very young children, chest and other x-rays can provide the only practical method for identifying and assessing trauma, such as from accidents or mishandling of the child, including child abuse cases such as shaken-baby syndrome and the like. In such cases, enhancement of rib and other bone structures can be of particular value for identifying rib fractures and related bone damage. Utilities that help to provide a more accurate diagnosis and assessment of rib trauma and injury can help to increase staff confidence as to whether or not intervention is required as well as providing evidence in abuse cases. In addition, proper levels of enhancement can help to reduce the need for retakes and consequent added radiation exposure to the patient.
Conventional chest x-ray enhancement processing identifies the enclosed lung field content and suppresses surrounding rib content that obstructs image content of the lung tissue. For trauma identification and assessment, however, somewhat a reverse of this processing approach is needed. That is, the full rib cage, particularly posterior regions, must be identified and enhanced to allow better visibility of fractures and related conditions. This includes portions of the skeletal structure that lie outside the lung area or the area typically associated with a lung mask. It can be appreciated that the problems of rib identification and segmentation can be fairly complex due to the need to identify the full extent of the rib cage and related skeletal structure within and outside the lung regions, including areas over the heart region, subdiaphragmatic regions, and including bony and connective cartilaginous structures that link the ribs to the spine.
It can be appreciated that there is a need for methods that detect and enhance rib and other bone content in radiological images.